Getting all mapped Entities from EntityManager

Question

I have a piece of maintenance code that should grant select privileges to a certain user at certain points of time:

grant select on A_DB.A_TABLE to READ_ONLY_USER;

I want to do this for all tables. I could use select * from tab in Oracle or show tables in MySQL to get the complete list and then move on like that.

But since I already have the javax.persistence.EntityManager Object at hand, I wondered if there is another way to get at all the mapped Entities, the Manager knows about (I am using Hibernate under the hood).

Answer 1

There are two ways that I can see getting all of the mapped entities and their corresponding SQL tables (there may be others).

The most straightfoward is if you can use your Hibernate Configuration object:

    for(Iterator it = config.getClassMappings(); it.hasNext();){
        PersistentClass pc = (PersistentClass) it.next();
        System.out.println(pc.getEntityName() + "\t" + pc.getTable().getName());
    }

Alternatively, you can do a little more casting and get this same information out of the SessionFactory too:

    Map<String, ClassMetadata>  map = (Map<String, ClassMetadata>) sessionFactory.getAllClassMetadata();
    for(String entityName : map.keySet()){
        SessionFactoryImpl sfImpl = (SessionFactoryImpl) sessionFactory;
        String tableName = ((AbstractEntityPersister)sfImpl.getEntityPersister(entityName)).getTableName();
        System.out.println(entityName + "\t" + tableName);
    }